Technical Field
The present disclosure relates generally to ultrasonic surgical instruments. More specifically, the present disclosure relates to ultrasonic surgical instruments having an end effector configured to effect tissue dissection, cutting, coagulation, ligation and/or hemostatis and having a microelectromechanical system incorporated therein (“MEMS”), which instrument can be used in open as well as laparoscopic or endoscopic surgical procedures.
Background of Related Art
Ultrasonic instruments for surgical use are well known and are used in a variety of surgical procedures for dissecting, cutting, ligating, effecting coagulation in, and/or effecting hemostasis in tissue. Typically, ultrasonic surgical instruments include a handpiece for grasping the instrument, a transducer attached to the proximal end of the handpiece, and a vibration coupler extending from the transducer through a body of the instrument to an end effector of the instrument. The transducer generates vibrations in the ultrasonic frequency range which are transmitted from the handpiece of the instrument to the end effector via the vibration coupler. This configuration, although effective in some applications, has several drawbacks. For example, the power of the instrument is attenuated when ultrasonic energy is transmitted from a proximal end of a device to a distal end of the device. Further, power losses are enhanced at couplings and seals of the instrument. As such, a large, heavy transducer is required to operate known surgical instruments. Moreover, contact between the vibration coupler and stationary components of the instrument result in mechanical faults in the instrument. Finally, the vibration coupler acts as a pump which draws bodily fluids from the distal end of the instrument to the proximal end of the instrument thereby making sterilization of the instrument after use difficult.
The use of an elongated vibration coupler also limits the operational features of the instrument available to a surgeon. More specifically, because the vibration coupler transmits vibrations from the transducer to the end effector, the inclusion of an articulation joint into the vibration coupler is difficult and inefficient. Accordingly, known ultrasonic instruments typically do not include articulating end effectors. Moreover, because the vibrations are transmitted from the transducer at the proximal end of the instrument to the distal end of the instrument, along a stiff vibration coupler, e.g., an elongated titanium rod, vibration energy is transmitted primarily along the rod in longitudinal waves. Any transverse vibrations that do occur as the energy is transmitted along the length of the vibration coupler reduces the overall efficiency of the system.